SAP HANA is a popular in-memory DBMS that includes storage services (Data Warehouse) and analytics, built-in middleware, an application server, a platform for customizing or developing new utilities. By eliminating the delays of traditional DBMS with SAP HANA, you can greatly increase the performance of systems, transaction processing (OLTP) and business intelligence (OLAP).
You can deploy SAP HANA in Appliance and TDI modes (if we talk about productive environments). For each option, the manufacturer has its own requirements. In this post, we will talk about the advantages and disadvantages of different options, as well as for clarity, about our real projects with SAP HANA.
SAP HANA consists of 3 main components - Host, Instance and System.
Host is a server or operating environment for running the SAP HANA DBMS. Its required components are CPU, RAM, storage, network, and OS. The host provides links to installation directories, data directories, log directories, or directly to the storage system. At the same time, the storage system for installing SAP HANA does not have to be located on the host. If the system has several hosts, either a shared storage will be required, or one that is available on demand from all hosts.
Instance is a set of SAP HANA system components installed on a single host. The main components are Index Server and Name Server. The first one, which is also called the "working server", processes requests, manages the actual data stores and database engines. The Name Server stores information about the topology of the SAP HANA installationβwhere the components are running and what data is on the server.
System is one or more instances with the same number. In fact, this is a separate element that can be enabled, disabled or copied (backed up). The data is distributed in the memory of the various servers that make up the SAP HANA system.
The system can be configured as single-host (one instance per host) or multi-host, distributed (several SAP HANA instances distributed across multiple hosts, with one instance per host). In multi-host systems, each instance must have the same number. A SAP HANA system is identified by a System ID (SID), a unique number consisting of three alphanumeric characters.
SAP HANA virtualization
One of the main limitations of SAP HANA is that it supports only one system - one instance with a unique server SID. Virtualization can be used to make better use of hardware or reduce the number of servers in a data center. This way, other landscapes can coexist on the same server with systems that have lesser requirements (non-productive systems). For a standby HA/DR server, virtualization can improve the speed of switching between productive and non-productive virtual machines.
SAP HANA includes support for the VMWare ESX hypervisor. This means that different SAP HANA systems - SAP HANA installations with different SIDs - can coexist on the same host (common physical server) in different virtual machines. Each virtual machine must run on a supported OS.
For productive environments, SAP HANA virtualization has serious limitations:
- Scale-out scaling is not supported - virtualization can only be used with Scale-Up systems, be it BwoH / DM / SoH or βpureβ SoH;
- virtualization must be carried out within the rules established for Appliance or TDI devices;
- There can only be one virtual machine in General Availability (GA) - companies wishing to use virtualization with HANA production environments must participate in the Controlled Availability program with SAP.
In non-productive environments where these limitations do not exist, virtualization can be used to optimize hardware utilization.
SAP HANA topologies
Let's move on to deploying SAP HANA. Two topologies are defined here.
- Scale-up is one big server. As the HANA base grows, so does the server itself: the amount of CPU and memory increases. In High Availability (HA) and Disaster Recovery (DR) solutions, standby or failover servers must match the performance of productive servers.
- Scale-out - the entire volume of the SAP HANA system is distributed over several identical servers. The master server contains information for the Index Server and Name Server. Slave servers do not contain this data - except for the server that takes over the functions of the Master in the event of a failure at the main server. Working servers (Index Servers) manage the data segments that are assigned to them, and also respond to requests. Name Servers are aware of how data is distributed between production servers. In the case of HANA growth, one more node is simply added to the current server configuration. In such a topology, it is enough to have one backup node to ensure the security of the entire server.
SAP hardware requirements
SAP has mandatory requirements for HANA hardware. They concern productive environments - for non-prod, minimal characteristics are enough. So, here are the requirements for productive environments:
- CPU Intel Xeon v5 (SkyLake) / 8880/90/94 v4 (Broadwell)
- from 128 GB RAM for BW applications with 2 CPUs, 256 GB with 4+ CPUs;
Deploying SAP HANA in Appliance and TDI modes
Now let's move on to practice and talk about how to implement SAP HANA in Appliance and TDI modes. For this, we use our SAP HANA platforms based on BullSequana S and Bullion S servers, which are certified by SAP to work in these modes.
A little information about the products. BullSequana S based on Intel Xeon Scalable includes various models, up to 32 CPUs in one server. The server is built on a modular design that provides scalability up to 32 CPUs and the same number of GPUs. RAM - from 64 GB to 48 TB. BullSequana S features include enterprise AI support for improved performance, accelerated data analytics, improved in-memory computing, virtualization and cloud upgrades.
Bullion S ships with Intel Xeon E7 v4 Family CPUs. The maximum number of processors is 16. RAM is scalable from 128 GB to 24 TB. A large number of RAS features provide high availability for critical infrastructures like SAP HANA. Bullion S is suitable for bulk data center consolidation, in-memory applications, mainframe or legacy system migration.
SAP HANA Appliance
Appliance is a pre-configured solution that includes a server, storage and turnkey implementation software package, with a centralized support service and an agreed level of performance. Here, HANA comes as pre-configured hardware and software, fully integrated and certified. Appliance mode is ready to be installed in the data center, and the operating system, SAP HANA, and (if required) an additional VMWare instance are already configured and installed.
SAP certification defines the guaranteed performance level, as well as the CPU model, RAM and storage capacity. Once certified, the configuration cannot be changed without voiding the warranty. To scale the HANA platform, SAP offers three options.
- Scale-Up BWoH/DM/SoH β vertical scaling, which is suitable for single systems (single SID). Appliances grow at 256/384 GB starting with SAP HANA SPS 11. This ratio shows the maximum capacity supported by a single CPU and is common to the entire list of certified Appliances. Scale-up BWoH/DM/SoH Appliance is best suited for BW on HANA (BWoH), Data Mart (DM) and SAP Suite on HANA (SoH) applications.
- Scale Up SoH - This is a lightweight version of the previous model, with fewer restrictions on the amount of RAM. It is still a scale-up server, but the maximum amount of RAM for 2 processors is already 1536 GB (up to SPS11) and 3 TB (SPS12+). Only suitable for SoH.
- scale-out is a scale-out option, a system that supports multi-server configurations. Horizontal scaling is optimal for BW and - with some limitations - for SoH.
In the BullSequana S and Bullion S servers, vertical scaling is the main one, as it has fewer operational restrictions and requires less administration. Appliance mode has a large range of different devices.
BullSequana S Solutions for SAP HANA Appliance Mode
*Optional E7-8890/94v4
Bullion S Solutions for SAP HANA Appliance Mode
All Bull Appliance solutions since SAP HANA SPS 12 are certified. The equipment is installed in a standard 19-inch 42U rack, with two power supplies - internal PDUs. Servers certified by SAP:
- BullSequana S with Intel Xeon Skylake 8176, 8176M, 8180, 8180M (processors with the letter "M" support 128 GB memory modules). In terms of price-quality ratio, options with Intel 8176 look best
- Bullion S with Intel Xeon E7-8880 v4, 8890 and 8894.
The storage connects directly to the server via FC ports, so no SAN switches are needed here. They can be useful for accessing systems connected to a LAN or SAN.
Here is an example EMC Unity 450F storage configuration in our setup:
- Height: 5U (DPE 3U (25Γ2,5β³ HDD/SSD) + DAE 2U (25Γ2,5β³ HDD/SSD))
- Controllers: 2
- Drives: 6 to 250 SAS SSDs, 600 GB to 15.36 TB each
- RAID: level 5 (8+1), 4 RAID groups
- Interface: 4 FCs per controller, 8 or 16 Gbps each
- Software: Unisphere Block Suite
Appliance is a solid deployment option, but it has a big drawback: little freedom in hardware configuration. In addition, this option may require changes in the processes of the IT department.
SAP HANA TDI
An alternative to Appliance is the TDI (Tailored Data center Integration) mode, in which you can select specific manufacturers and infrastructure components depending on the wishes of the customer - taking into account the tasks and workload to be performed. For example, a SAN can be reused in the data center, with some disks dedicated to the HANA installation.
Compared to the Appliance, the TDI mode gives the user much more freedom to meet their requirements. This greatly simplifies the integration of HANA into the data center - you can build your own customized infrastructure. For example, vary the type and number of processors depending on the load.
The recommended capacity calculation is SAP Quick Sizer, a simple tool that provides CPU and memory requirements for different workloads in SAP HANA. You can then contact SAP Active Global Support to plan your IT landscape. After that, the SAP HANA hardware partner converts the calculation results into different possible system configurations - both on top-end and on simpler hardware. In TDI mode for servers it is acceptable to use Intel E7 CPUs, including Intel Broadwell E7 and Skylake-SP (Platinum, Gold, Silver with 8 or more cores per processor), as well as IBM Power8/ 9.
Servers are delivered without storage, switches and racks, but the hardware requirements remain the same as in Appliance mode - the same single nodes, solutions with vertical or horizontal scaling. SAP requires that only certified servers, storage systems and switches were used, but it's not scary - most manufacturers have almost all equipment certified.
Performance testing should be done using HWCCT (Hardware Configuration Check Tool) tests, which allow you to check compliance with certain SAP KPIs. And there is a non-hardware requirement: HANA, OS and hypervisor (optional) must be installed by SAP certified specialists. Only systems that comply with all of the above rules can receive performance-related support from SAP.
The BullSequana S server line in TDI mode is similar to the line in Appliance mode, but without storage, switches and rack. You can install any storage system from the list of certified SAPs to them - VNX, XtremIO, NetApp and others. For example, if the VNX5400 meets SAP HANA performance requirements, you can connect Dell EMC Unity 450F storage as part of the TDI configuration. If necessary, FC adapters (1 or 10 Gb / s) are installed, as well as Ethernet switches.
Now, in order for you to more clearly present the described modes, we will talk about several of our real cases.
Appliance + TDI: HANA for online store
The online store Mall.cz, which is part of the Mall Group, was founded in 2000. It has branches in the Czech Republic, Slovakia, Poland, Hungary, Slovenia, Croatia and Romania. It is the largest online store in the country, selling up to 75 products per day, its revenue in 2017 amounted to about 280 million euros.
Data center infrastructure upgrade was required due to migration to SAP HANA. Estimated sizing was 2x6TB for prod environments and 6TB for test/dev environments. This required a disaster recovery solution for a productive SAP HANA environment in an active-active cluster.
At the time of the tender announcement, the customer had a system for SAP based on standard rack and blade servers. Two data centers, located at a distance of about 10 km from each other, were equipped with different storage systems - IBM SVC, HP and Dell. Key systems were in disaster recovery mode.
The customer first requested a certified solution in Appliance mode for SAP HANA for all systems (Production and test/dev environments) growing up to 12TB. But due to budget constraints, other options began to be considered - for example, more CPUs with smaller RAM modules (64 GB modules instead of 128 GB modules). In addition, joint storage for Production and test / dev environments was considered to optimize the price.
Agreed on 4 CPUs and 6 TB of RAM for the Production environment, with room for growth. For test / dev environments in TDI mode, we decided to get by with less expensive CPUs - we got 8 CPUs and 6 TB of RAM. Due to more features requested by the customer - replication, backup, shared Production and test / dev environments on the second site - instead of internal disks, DellEMC Unity storage was used in a full-flash configuration. In addition, the customer requested a disaster recovery solution based on HANA System Replication (HSR) with a quorum node at a third site.
The final configuration for the Prod environment consisted of a BullSequana S400 server with an Intel Xeon P8176M (28 cores, 2.10 GHz, 165 W) and 6 TB of RAM. Storage - Unity 450F 10x 3.84 TB. For disaster recovery purposes for the Prod environment, we used BullSequana S400 on an Intel Xeon P8176M (28 cores, 2.10 GHz, 165 W) with 6 TB of RAM. For the test / dev environment, we took the BullSequana S800 server with Intel Xeon P8153 (16 cores, 2.00 GHz, 125 W) and 6 TB of RAM plus Unity 450F 15x 3.84 TB storage. As a quorum, application servers (VxRail Solution) and a backup solution (DataDomain), our specialists installed and configured DellEMC servers.
The equipment is ready for a future upgrade. The customer expects HANA sizing to grow in 2019, and all he has to do is install new modules in the racks.
Appliance: HANA for a major tourism integrator
This time our client was a major IT service provider that develops technological solutions for travel companies. The customer launched an ambitious SAP HANA project to implement a new billing system. Required Appliance mode solution with 8 TB of RAM for Production and PreProd environments. As recommended by SAP, the customer chose the vertical scaling option.
Implementation of the hardware infrastructure based on devices certified in the Appliance mode for SAP HANA became a key task. The priority criteria were cost effectiveness, high performance, scalability and high data availability.
We proposed and implemented a SAP-certified solution that includes two Bullion S16 servers - for Prod and PreProd environments. The equipment runs on Intel Xeon E7-v4 8890 processors (24 cores, 2.20 GHz, 165 W) and is equipped with 16 TB of RAM. For BW and Dev/Test environments, nine Bullion S4 servers (22 cores, 2.20 GHz, 150 W) with 4 TB of RAM were installed. A hybrid EMC Unity was used as a storage system.
This solution provides scaling support for all elements of the device - for example, up to 16 sockets with an Intel Xeon E7-v4 CPU. Administration in this configuration is simplified - in particular, for reconfiguring or splitting the server into partitions.
Appliance + TDI: HANA for steelmakers
MMC Norilsk Nickel, one of the largest producers of nickel and palladium, decided to upgrade its SAP HANA hardware platform to ensure the operation of critical business applications and projects. It required expanding the existing landscape in terms of computing power. One of the main conditions put forward by the customer was the high availability of the platform - despite the hardware limitations.
For productive environments, we used a Bullion S8 server and storage in SAP HANA Appliance mode. For HA and test/dev, the platform was deployed in TDI mode. We used one Bull Bullion S8 server, two Bull Bullion S6 servers and a hybrid storage system. This combination has significantly increased the speed of applications in the SAP landscape, increased the amount of computing power and storage resources, and minimized operating costs. It is important that the client still has the ability to scale up to 16 CPUs.
Welcome to SAP Forum
In this post, we have taken a look at deploying SAP HANA in different ways, trying to highlight the advantages and disadvantages of the available options. If you have any questions about implementing SAP HANA, we will be happy to answer them in the comments.
We invite everyone who is interested in Bull solutions and the possibilities of their implementation under SAP HANA to the largest SAP event of the year: SAP Forum 17 will be held in Moscow on April 2019. We are waiting for you at our booth in the IoT zone: we will tell you a lot of interesting things, as well as play a lot of prizes.
See you on the forum!
Source: habr.com